Estimation of sensor response characteristics is necessary to satisfy requirements on allowable response time for nuclear power plants. The methodology currently used includes direct and indirect measurements, each of them having its advantages and disadvantages. The objective of this work is to compare the time response measurements of temperature and pressure sensors which the Brazilian Angra 1 nuclear power plant obtained using direct and indirect methodologies. Direct methods give more precise results but need special equipment to be carried out and they interfere with the reactor operation. Indirect methodology is most practical to perform; it does not interfere with the reactor operation because the sensors do not have to be out of operation. On the other hand, since the parameter identification depends on the noise characteristics, there are cases where indirect methodology is not suitable to predict time response.
Keywords: time response measurements, temperature sensors, pressure sensors, loop current step response, LCSR, nuclear power plants, nuclear energy, Brazil, nuclear reactors